Sheet having a transferable coating containing magnetizable material



2,744,031 Patented May 1,1956

SHEET HAVING A TRANSFERABLE COATEN G CONTAINING MAGNETIZAELE MATERIAL No Drawing. Application October 15, 1945, Serial No. 121,635

Claims. ((11. 117-36) This invention relates to a sheet having transferable coating containing magnetizable material, and more particularly pertains to such a sheet through which a marking impression may be made and in the coating of which the magnetizable material is present in small particle form as a dispersion in a waxy medium.

Such a sheet is usefu as a means for transferring magnetizable spots or magnetized spots to record material, such spots by their location or number on a piece of rec ord material representing selected data. Such record material with unmagnctized spots is disclosed in application for United States Letters Patent, Serial No. 97,222 of Konrad Ranch, filed June 4, 1949, now abandoned, and a method of using such record material is disclosed in application for United States Letters Patent, Serial No. 102,843, of the same Konrad Rauch, filed July 2, 1949, now abandoned.

The novel sheet of this invention is used in a manner similar to the way carbon transfer paper is used, that is, it is placed, coated side down, on top of the coated sheet at points where marks are to be left on the record sheet, a portion of the coating being transferred to the record material because of the applied pressure.

The transferred coating material has carried therewith the proportionate amount of the dispersed magnetizable substance, be it in the magnetized or unmagnetized condition. If the particles are in magnetized condition in the transfer sheet the particles transferred to the record sheet will remain so, as the transfer of materials is made by pressure or impact forces, such as would occur through use of a stylus or a type member, which will not disturb the orientation of the particles suliiciently to seriously interfere with the mass effect. The magnetization of the sheet should, to get best results, be made with the poles of all the magnetized particles oriented in the same direction parallel with plane of the sheet and not perpendicular to it. This may be easily done by drawing a magnet across the front or rear surface of the sheet.

Therefore, it is an object of this invention to provide a sheet with a transfer coating including magnetizable particles dispersed in the coating.

Another object of the invention is to provide such a coated sheet with the particles normally unmagnetized therein.

Another object of the invention is to provide such a coated sheet with the particles normally magnetized therein.

With these and incidental objects in View which will become apparent, the invention will be described as to a preferred and other embodiments all coming within the p inciple thereof as will be claimed.

Tin. pref :red sheet used, a to which the coating is applied, is paper, although other thin sheeting whether of woven or film construction, and through which a printing or marking impression may be made, may be used. For example, finely woven cloth or cellulose acetate film may be used instead of paper.

The preferred coating waxy base is made of the fol lowing ingredients: petrolatum having a melting point of between and Fahrenheit, an apparent viscosity at 80 Fahrenheit of between 2500 and 4500 Saybolt Universal seconds at a rate of shear of 1200 reciprocal seconds, and a neutralization number of 0.05 as determined by American Society for Testing 1V aterials method; parathn wax having a melting point of between 125 and 30 Fahrenheit; vegetable fiber wax having a melting point of approximately 173 Fahrenheit, a saponiiication number of approximately 65 and an iodine number of 20 to 30; yellow beeswax having a specific gravity of 0.95 to 0.97 at centigrade, a melting point of be tween 62 and 65 centigracie, an acid value of between 17' and 24, a saponilication value of 87 to 104, and an ester value of 70 to 80, all as determined by the U. S. Pharmacopoeia; Ouricury wax having a melting point of 174l82 Fahrenheit, a. saponirication number of 76 to 2.0, and an iodine number of 9-10, all as determined by American Society for Testin Materials methods; and naphthenic petroleum oil. having a flash point (open cup tester) of 350 Fahrenheit minimum, a fire point (open cup tester) of 400 Fahrenheit minimum, a pour point of 10 Fahrenheit, a viscosity of 100 Fahrenheit of (Sayboit) 300 to 325, and a neutralization number of'.05, all as determined by American Society for Testing Materials methods. These materials are used in the following proportions by weight:

into this waxy base is mixed the magnetizable particles, which, preferably, is in the form of finely powdered magnetic iron oxide, finely powdered iron, or both. As much should be introduced as the waxy base will hold and still retain its coating and transfer characteristics. About 50 pounds of either iron oxide or iron powder may be incorporated in the above mentioned 30.1 pound batch of the waxy base. The proportions of magnetizable material and waxy base may vary considerably from this figure.

The magnetic iron oxide may be magnetized while in the coating and so transferred in the magnetized state to the record material to be marked. Such marks may be sensed as magnetic spots by standard pick-up appart tus in which such merits generate a current as they pass over the poles of an electromaguet. The unmagnetized iron oxide marks may be magnetized on the record material before being so sensed. The iron powder marks, while they may not be sensed as a magnetic spot, may be sensed as areas of increased magnetic permeability.

The magnetizable par"cle size, measured by diameters, preferably is or" the order of 1 to 5 microns.

The coating is applied to the sheet hot by means of a coating machine like those used for carbon transfer coating.

As stated, this transfer coated sheet finds its primary use as a carrier of magnetizable material to be transferred to record material by pressure or impact.

The particular waxy base and magnetizable materials named are not to be deemed as limitin the invention as many equivalents are available and Well-lcnown to those skilled in the particular arts involved.

What is claimed is:

1. A transfer sheet including,

in combination, a base sheet through which a printing or marking impression may be made; and a pressure-transferable magnetizable coating on a surface thereof, which may be locally transferred by placing the transfer sheet onto an undersheet so the transfer sheet coating is in contact therewith and making a printing or marking impression through said transfer sheet, and said coating being of waxy material having dispersed therein fine particles of magnetizaole material, the magnetizable material being of microscopic particle size and constituting the major portion by Weight of the weight of the entire coating.

2. The sheet of claim 1 in which the particles are magnetic iron oxide.

3. The sheet of claim 1 in which the magnetizable material includes magnetic iron oxide.

4. The sheet of claim 1 in which the magnetizable .1

material includes particles of iron, ranging from 1 to 5 microns in diameter.

5. The sheet of claim 1 in which the magnetizable material includes particles of magnetizable iron oxide with particles of iron.

6. A sheet through which a printing or marking impression may be made, said sheet having coated on a surface thereof a waxy substance having dispersed therein microscopic particles of magnetizable material, said Waxy substance and contained magnetizable material being transferable locally by a printing or marking impression applied to the sheet.

7. The sheet of claim 6 which has the particles magnetized.

8. The sheet of claim 1, which has the particles magnetized.

References Cited in the file of this patent UNITED STATES PATENTS 482,451 Koskul Sept. 13, 1892 1,800,560 Neidich Apr. 14, 1931 1,815,010 Pollock et al July 14, 1931 1,847,860 Best Mar. 1, 1932 1,885,388 Taylor et a1. Nov. 1, 1932 1,889,380 Ruben Nov. 29, 1932 2,199,526 McCowen May 7, 1940 2,418,479 Pratt et a1. Apr. 8, 1947 2,479,094 Bicknell Aug. 16, 1949 2,525,601 Howell Oct. 10, 1950 2,584,318 Allyn Feb. 5, 1952 FOREIGN PATENTS 340,705 Great Britain Jan. 8, 1931 459,884 Great Britain J an. 18, 1937 466,023 Great Britain May 18, 1937 OTHER REFERENCES Bennet: Commercial Waxes, Chemical Publishing Co., Brooklyn, N. Y., 1944, pages 367-368. 

1. A TRANSFER SHEET INCLUDING, IN COMBINATION, A BASE SHEET THROUGH WHICH A PRINTING OF MARKING IMPRESSION MAY BE MADE, AND A PRESSURE-TRANSFERABLE MAGNETIZABLE COATING ON A SURFACE THEREOF, WHICH MAY BE LOCALLY TRANSFERRED BY PLACING THE TRANSFER SHEET ONTO AN UNDERSHEET SO THE TRANSFER SHEET COATING IS IN CONTACT THEREWITH AND MAKING A PRINTING OR MARKING IMPRESSION THROUGH SAID TRANSFER SHEET, AND SAID COATING BEING OF WAXY MATERIAL HAVING DISPERSED THEREIN FINE PARTICLES OF MAGNETIZABLE MATERIAL, THE MAGNETIZABLE MATERIAL BEING OF MICROSCOPIC PARTICLE SIZE AND CONSTITUTING THE MAJOR PORTION BY WEIGHT OF THE WEIGHT OF THE ENTIRE COATING. 